"The Impact of Sea Ice on the Climate System"

 by Tido Semmler, PhD, Met Eireann

Venue: TCD Botany Theatre – Trinity College, Dublin

Date / Time: Thursday 26th February at 8 PM

Summary:

In recent years the Arctic sea ice has declined considerably. In September 2007 a record low in sea ice extent has been reached and September 2008 has shown the second lowest sea ice extent since satellite monitoring started end of the 1970's. From 1979 to 2008 the rate of decline in sea ice extent has been 11.7% per decade. In January the sea ice extent has declined by 3.1% per decade from 1979 to 2009. Climate simulations with coupled atmosphere-ocean-sea-ice models for the future predict a further declining trend of the Arctic sea ice, some of them suggesting an ice-free Arctic in summer for the mid of this century. The question addressed in this lecture is how such drastic changes in the sea-ice extent could influence the climate of the mid-latitudes. Circulation changes far beyond the Arctic itself are likely due to changes in the meridional temperature gradient which could lead to different wind and rainfall patterns in the mid-latitudes. The results of sensitivity studies with the EC-EARTH-IFS global climate model will be presented.